Printing mechanism having a rim of rotating type levers



Dec. 24, 1968 M. FLEISCHER ET AL 3,417,847

PRINTING MECHANISM HAVING A RIM OF ROTATING TYPE LEVERS Filed March 20, 1967 5 $heets$heet l INVENTORS NANFREO FLE/SCHER FOL/(ER GALASK M Wd ATTORNEY Dec. 24, 1968 M FLEISCHER ET AL 3,417,847

PRINTING MECHANISM HAVING A RIM OF ROTATING TYPE LEVERS 3 Sheets-Sheet Filed March 20, 1967 Fig. .2

INVENTORS MANFRED FLE/SCH'R AOLKER cm. ASK' WM JM 4 ATTORNEY Dec. 24, 1968 M- FLEISCHER ET AL PRINTING MECHANISM HAVING A RIM OF ROTATING TYPE LEVERS Filed March 20, 1967 3 Sheets-Sheet 5 INVENTORS MANFRED ae/scfl-sn FOLKER 6A LA SkE BY J ATTORNEY United States Patent 3,417,847 PRINTING MECHANISM HAVING A RIM 0F ROTATING TYPE LEVERS Manfred Fleischer and Folker Galaske, Pforzheim, Germany, assignors to International Standard Electric Corporation, New York, N.Y., a corporation of Delaware Filed Mar. 20, 1967, Ser. No. 624,527 Claims priority, application Germany, Apr. 7, 1966, St 25,216 7 Claims. (Cl. 197--18) ABSTRACT OF THE DISCLOSURE A printing mechanism in which the printing elements consist of a rim of type levers arranged radially in relation to their axis of rotation. The arrangement with respect to the printing plane being such that the extended center line of this axis intersects at the printing point in the printing plane.

The present invention relates to a printing mechanism for effecting the serial data recording in which the printing element consists of a rim of type levers arranged radially in relation to the axis of rotation. The type levers are selected individually, to strike a printing base, which is a cylindrical body having a horizontally or vertically arranged shaft.

Conventional printing mechanisms of this kind, for example, German Patent No. 423,548, have certain disadvantages and one is that the achievable printing speed is relatively low, because the rim of type levers must first be brought to a standstill prior to each printing operation.

According to the present invention, this disadvantage is overcome by providing printing out of the movement which eliminates the problem of the high relative movement between the type and the recording medium as is done in the so'called on-the-fly printing. According to the invention this is accomplished by the rim of type levers rotating at a constant speed, and the axis of rotation of the rim of type levers is arranged, in relation to the printing base or support, so that the extended centre line of the axis (shaft) intersects with the vertical line on the printing point. This point of intersection lies in or approximately in the printing plane. This allows printing to occur each time on the centre line of the axis such that the angular variation of the struck type, with respect to the recording medium, has little effect for the time duration of the printing operation, and print is produced.

An exemplified embodiment of the invention will now be explained in detail with reference to FIGS. 1 to 3 of the accompanying drawings, in which:

FIG. 1 shows in a simplified representation, the printing mechanism in a side view taken in a partial sectional elevation;

FIG. 2 shows a top view of selected portions of FIG. 1 to illustrate the cam plates (curved tracks); and

FIG. 3 shows in a developmental view, the optionally controllable rotational tracks of the cam plate sensing elements associated with the type levers.

Referring to FIG. 1, the individual type levers 5 are supported in a rim-shaped fashion in the radially arranged indentations of an annular type-lever bearing 3. In common to all type levers 5 is the type-lever support 6 resting on a ring console 6a, and a dome-shaped type lever guide 7 with the guide slots 7a. With the aid of this guide the Coriolis force, which acts transversely in relation to the striking movement of the type-levers, is extensively rendered ineffective. The console 6a and the guide 7 are centrically led through the upper portion of the type lever bearing 3 and are supported on a ring shoulder 3a. A (not shown) clamping device prevents the parts 6 and 7 from sliding off or shifting on their own. With each type lever 5, there is associated a transfer lever 8 which, by means of a gear mesh, are in a form-locking connection or engagement with one another. Each of the transfer levers 8 is provided at its other end with a slide member So having a shuttle-type cross-section. These slide members radially project out of the circumference of the typelever bearing 3,and serve to bring the type levers, which are selected by stationary control means 12, into connection with the stationarily arranged cam plates (curved tracks) 9 and 10, into the impact (striking) position, and into position for returning the type levers to normal.

The type-lever bearing 3 is rigidly connected to a vertical axis of rotation 4. According to the present invention, this axis is subjected to a continuous drive, and is arranged so that the extension of the centre line Y of the axis coincides with the tangent line extending through the centre point of printing P at the circumference of the platen 1 or the paper track 2 which is led round it. With this arrangement it is possible to achieve a clean printing, because of combination of the centre of rotation being at the printing point, and the angular variation resulting from the continuously rotating rim of type levers 13, of the type bar 5a in the printing position, has very little effect upon the font of type during the time required for the printing operation.

As shown in FIG. 3, the selection of the type bar 5a into the printing position is effected with the aid of control means 12. The respectively associated sliding member 8a is deflected by a mechanical or electrical deflector (separator) from the normal track of rotation, as indicated by the dot-and-dash line, onto the track indicated by the dash line. Due to this deflection, the respective sliding member 8a is brought onto the inclined portion of the striking cam plate 9 which causes the associated type lever 5 as shown in FIG. 1 to be brought into striking (printing) position. After the printing, which is effected at point P, the sliding member 8a, due to the continuous rotation of the rim of type levers, enters the range of the reset cam plate 10 and returns to the normal non-printing position.

FIG. 2 shows the arrangement of the two cam plates 9 and 10, as well as the control means 12 with respect to the printing platen 1 and the printing point P. The cam plates 9 and 10, with respect to the rotating rim of type levers 13 rotating in the direction indicated by the arrow, are mounted on stationary cam plate bearings 11 (FIG. 1) and are adjustible within certain limits for exactly defining the printing time position. The striking cam plate 9 has a pitch which is almost constant throughout its entire length, so that very favourable acceleration values are obtained. Because of the efiective centrifugal forces, it is possible to eliminate spring mounting of type lever. The position of the centre of gravity of both the type levers 5 and of the transfer levers 8 is selected so that the type levers, during rotation, are retained by centrifugal force in their position against the type-lever support 6. Moreover, the sliding members 8a, because of the moment of inertia occurring during the printing and the resetting movement, reliable adherence to the cam plates is assured.

For printing, any conventional ink ribbon may be used or, due to the rotation of the rim of type levers 13, a conventional type of ink roller may be utilized so that the types are inked While passing.

Due to the rim-shaped arrangement of the type levers, it is possible to accommodate a substantially greater number of type levers than in the conventional types of typelever machines. In the case of a requirement for a greater number of letters and figures, it is not necessary to provide a double occupancy of figures or letters on the typelevers, and the conventional shifting from one case group to the other is thereby eliminated.

Besides platen 1 as shown, it is also possible to use a printing wheel with a vertically standing axis of rotation, or a printing bar having a plane surface, as is customary in strip chart recorders, as the printing base. These are then arranged in a similar way as described hereinbefore, with respect to the centre line of the axis of rotation 4.

In view of reducing the lengths of the type levers, of diminishing the swivel angle of the type levers, and consequently, of a possible increase of the operating frequency, it is possible to provide the rim of type levers 13 with a position which is inclined towards the printing point with respect to vertically standing axis 4.

In this case, the type-lever bearing 3 is connected in a form-locking manner to the axis of rotation 4 via a Cardan-joint-like intermediate member.

While we have described above the principles of the invention in connection with specific apparatus, it is to be clearly understood that this description is only by way of example and not as a limitation to the scope of our invention as set forth in the accompanying claims.

What is claimed is:

1. A print mechanism comprising:

means for supporting a print receiving member at a printing point;

a printing element including a rim of type levers carrying type heads and rotating about an axis at a constant speed;

each of said type levers being arranged radially in relation to the axis of rotation of said rim and being pivotally mounted to the rim at the end of the type lever which is normally closest said axis of rotation, said axis of rotation passing through said printing point;

the type head on a selected type lever being arranged to move toward said axis of rotation during its movement from a normal rest position to said printing point; and

means for individually bringing said type levers into the printing position.

2. A mechanism according to claim 1, wherein said means for supporting a print receiving member is a platen, said axis of rotation is vertical, and said rim of type levers rotates below said platen and horizontally around the vertical axis of rotation.

3. A mechanism according to claim 2 including stationary guide means, said guide means causing said rim of type levers to assume a position inclined towards the printing point, and a shaft at the axis of rotation, said shaft being connected in a form-locking manner to each type of lever of said rim of type levers by means of a pivotly mounted transfer lever.

4. A mechanism according to claim 1 in which each type lever of said rim of type levers is in a form-locking connection with a transfer lever, said transfer lever including on one end a sliding member adapted to engage a pair of stationary supported cam plates, said cam plates arranged within the range of the rotational track of said sliding members, such that the selected type levers are brought into the printing position by one of said cam plates and returned to the normal position by the other of said cam plates.

5. A mechanism according to claim 4, in which said sliding members in a normal position define a circular track which is unaffected by said cam plates, and in which said sliding members in a selected position are deflected into a track extending over the cam plates.

6. A mechanism according to claim 5, wherein said type levers are guided, above their center by rotation, in the slots of a dom-shaped lever guide.

7. A mechanism according to claim 6, in which the position of the center of gravity of said type and transfer levers when at normal, is chosen so that the centrifugal forces are effective during rotation to retain said type levers with a suflicient pressure, in a counter-force position, on a type lever support.

References Cited UNITED STATES PATENTS 304,463 9/1884 Sheehy 197--18 871,145 11/1907 Richards 19718 1,864,088 6/1932 Morton 17827 2,127,507 8/1938 Fuchs 19753 2,139,700 12/1938 Slavin 19714 X 2,369,433 2/1945 Casey 19718 X 2,547,046 4/1951 Salmon 197-53 3,289,805 12/1966 Kleinschmidt et al. 19718 ROBERT E. PULFREY, Primary Examiner.

E. S. BURR, Assistant Examiner. 

